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Anabolic steroids cause a variety of side effects, among them a slight concentric left ventricular hypertrophy. The objective of the present study was to clarify if they also induce alterations in left ventricular function. 14 male body builders with substantial intake of anabolic steroids (users) were examined by standard echocardiography and cardiac tissue Doppler imaging. They were compared to 11 steroid-free strength athletes (non-users) and 15 sedentary control subjects. Users showed an increased left ventricular muscle mass index. The ratio of peak transmitral blood flow velocities during early diastolic filling and atrial contraction did not differ between groups (users: 1.4 +/- 0.3; non-users: 1.7 +/- 0.5; controls: 1.4 +/- 0.4). In contrast an analogous tissue Doppler parameter, the ratio of myocardial velocities during early and late ventricular filling in the basal septum, was significantly lower in users (1.2 +/- 0.4) when compared to non-users (1.6 +/- 0.5) or controls (1.6 +/- 0.6). The velocity gradient during myocardial E-wave in the posterior wall showed significantly lower values in users (3.8 +/- 1.3 1/s) as compared to controls (5.8 +/- 2.5 1/s). There were no differences in systolic function. Summarizing strength athletes abusing anabolic steroids show negative alterations in diastolic function.  相似文献   
33.
Summary.   Two reptilian paramyxoviruses, isolated from a neotropical rattlesnake (neotropical virus, NTV, ATCC VR-1408) and a bush viper (bush viper virus, BVV, ATCC VR-1409), respectively, were analysed to determine their taxonomic position among other reptilian paramyxoviruses investigated previously by Ahne et al. [7]. A 679 bp long region of the hemagglutinin-neuraminidase (HN) gene and a 627 bp long region of the large (L) gene were reverse transcribed, amplified by polymerase chain reaction (PCR), and sequenced. The deduced amino acid sequences were compared to mammalian paramyxoviruses belonging to the genera Respirovirus and Rubulavirus. The deduced amino acid sequences revealed 58.9 to 62% homology for the partial L protein and 41% to 47.1% homology for the partial HN protein. For phylogenetic analyses, a 518 bp L gene and a 352 bp HN gene fragment were used, both generating similar trees consisting of two distinct main groups, and some intermediate isolates. BVV clustered within group “b” while NTV clustered together with the intermediate ophidian paramyxovirus isolate Crot2-OH90. Received November 6, 2000 Accepted January 23, 2001  相似文献   
34.
For the purpose of investigating differences in terms of gender and methodology, a group of 80 healthy children engaged in leisure-time sport activities (male: n = 50; 10.9 +/- 1.1 years; female: n = 30; 11.5 +/- 1.1 years) was divided into 3 groups, which were then subjected to different ergometric procedures. In group I, boys and girls were compared in a bicycle ergometry in an upright seated position. In group II, a bicycle ergometry in upright seated position was compared with a bicycle ergometry in a supine position. In group III, a bicycle ergometry in upright seated position was compared with a treadmill exercise. Bicycle ergometry was started at 25 W; workload was increased in steps of 25 W every 3 min until the children felt exhausted. Results: No differences with respect to gender were found for maximum oxygen uptake, maximum heart rate and maximum lactate. The relevant parameters were also similar on submaximal levels of exercise intensity. All children reached a degree of thorough physical exhaustion at heart rates close to 200 X min-1. As in adults, maximum oxygen uptake decreased in the following order: treadmill exercise greater than bicycle ergometry in upright seated position greater than bicycle in supine position. Systolic and diastolic blood pressure on the various levels of exercise were lower than among adults.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
35.
Recently, in a cross-sectional study, a correlation of moderate degree was documented between serum BNP (brain natriuretic peptide) and exercise capacity in patients with chronic heart failure (CHF). However, it remains unknown if BNP, which increases in response to high myocardial wall stress, is sufficiently sensitive for changes in exercise capacity during clinical follow-up. To elucidate this, 42 CHF patients were recruited and randomized into a training (T; 58 +/- 10 years; n = 14 NYHA II; n = 5 NYHA III) and a control group (CO; 54 +/- 9, n = 17 NYHA II; n = 6 NYHA III). T carried out 12 weeks of endurance training on a cycle ergometer (4 sessions per week, 45 min duration). Venous blood sampling and cycle ergometry with simultaneous gas exchange measurements were carried out prior to and after the experimental phase. Due to its superior stability during laboratory procedures, NTproBNP was determined instead of BNP. Both proteins are secreted in equimolar amounts and share an identical diagnostic meaning. In both groups, NT-proBNP decreased slightly (T: from 1092 +/- 980 to 805 +/- 724 pg x ml(-1); CO: from 1075 +/- 1068 to 857 +/- 1138 pg x ml(-1); T vs CO: p = 0.65). Anaerobic threshold (AT) as a measure of exercise capacity went up in T (from 0.96 +/- 0.17 to 1.10 +/- 0.22 l x min(-1)) but remained almost constant in CO (pre: 1.02 +/- 0.27; post: 1.00 +/- 0.27 l x min(-1); T vs CO: p < 0.001). The correlation between changes in NT-proBNP and changes in AT remained insignificant (r = 0.02, p = 0.89)-even if only T was considered (r = 0.09, p = 0.72). Improved exercise capacity in CHF patients due to 3 months of endurance training is not reflected in the course of NT-proBNP. These findings are inconsistent with a sufficient sensitivity of this parameter to detect changes in exercise capacity during clinical follow-up. Changes in NT-proBNP beyond its spontaneous variability are more likely to be detected following therapeutical interventions which aim more clearly at the myocardium. In determining alterations of functional capacity ergometric testing cannot be replaced by serial determinations of NT-proBNP.  相似文献   
36.
Graeter TP  Kindermann M  Fries R  Langer F  Schäfers HJ 《Chest》2000,118(5):1271-1277
PURPOSE: Aortic valve preservation is a promising alternative to conventional composite replacement of aortic valve and ascending aorta. This approach may have a physiologic benefit compared with valve replacement similar to that seen in mitral valve reconstruction. We investigated aortic valve gradients at rest and during exercise in patients who had undergone valve-preserving aortic replacement and compared them with composite replacement of valve and aorta. METHODS: Four groups were studied: nine patients underwent composite valve replacement (group A: valve diameter, 23 to 27 mm), eight patients underwent remodeling of the aortic root (group B), and another nine patients had reimplantation of the aortic valve (group C). Healthy volunteers were studied as a control group (group D). Using continuous-wave Doppler echocardiography, all patients were examined on a bicycle ergometer for aortic valve gradients (0 to 75 W). RESULTS: There were no differences among the groups with respect to age, body surface, left ventricular end-diastolic diameter, fractional shortening, or left ventricular mass. Maximum resting gradients were significantly elevated in group A compared with groups B, C, and D (group A: 21.3 +/- 7.1 mm Hg; group B: 9.0 +/- 4.5 mm Hg; group C: 8.6 +/- 3.7 mm Hg; group D: 4.9 +/- 1.6 mm Hg; p < 0.05). At 75 W, group A exhibited significantly higher gradients than all other groups (group A: 31.3 +/- 7.5 mm Hg; group B: 13.9 +/- 6.6 mm Hg; group C: 12.8 +/- 3.5 mm Hg; group D: 9. 2 +/- 1.9 mm Hg; p < 0.05). There was no significant difference among the other groups. Both valve-preserving groups had only insignificantly higher gradients than the control group. CONCLUSION: Our data strongly support the suggestion that preserving the aortic valve restores nearly normal hemodynamic function of the aortic valve. Long-term observations will have to prove the clinical relevance of restoring physiologic aortic valve hemodynamics.  相似文献   
37.
38.
OBJECTIVES: Athlete's heart represents a structural and functional adaptation to regular endurance exercise. BACKGROUND: While left ventricular (LV) hypertrophy of the athlete's heart has been examined in many studies, the extent of right ventricular (RV) hypertrophy is still uncertain because of its complex shape and trabecular structure. To examine RV hypertrophy, we used magnetic resonance imaging (MRI) and hypothesized that athlete's heart is characterized by similar LV and RV hypertrophy. METHODS: The LV and RV mass, volume, and function in 21 male endurance athletes (A) (27 +/- 4 years; 70 +/- 8 kg; 178 +/- 7 cm; maximal oxygen uptake [VO(2)max]: 68 +/- 5 ml/min per kg) and 21 pair-matched untrained control subjects (C) (26 +/- 3 years; 71 +/- 9 kg; 178 +/- 6 cm; VO(2)max: 42 +/- 6 ml/min per kg) were analyzed by MRI (Magnetom Vision 1.5T, Siemens, Erlangen, Germany). RESULTS: Left ventricular masses: (A: 200 +/- 20 g; C: 148 +/- 17 g) and RV masses (A: 77 +/- 10 g; C: 56 +/- 8 g) differed significantly between the groups (p < 0.001). The LV and RV end-diastolic volumes (EDV) (LV-EDV 167 +/- 28 ml [A]; 125 +/- 16 ml [C]; RV-EDV 160 +/- 26 ml [A]; 128 +/- 10 ml [C]), and stroke volumes (SV) (LV-SV: 99 +/- 18 ml [A], 74 +/- 11 ml [C]; RV-SV: 102 +/- 18 ml [A], 79 +/- 8 ml [C]) were significantly different between the athletes and control subjects (p < 0.001), whereas ejection fractions (EF) (LV-EF: 59 +/- 3% [A]; 59 +/- 6% [C]; RV-EF: 63 +/- 3% [A], 62 +/- 3% [C]) and LV-to-RV ratios were similar for both groups (LV-to-RV mass: 2.6 +/- 0.2 [A], 2.6 +/- 0.3 [C]; LV-to-RV EDV: 1.05 +/- 0.14 [A], 0.99 +/- 0.14 [C]; LV-to-RV SV: 0.98 +/- 0.17 [A], 0.95 +/- 0.17 [C]; LV-to-RV EF: 0.93 +/- 0.07 [A], 0.96 +/- 0.10 [C]). CONCLUSIONS: Regular and extensive endurance training results in similar changes in LV and RV mass, volume, and function in endurance athletes. This leads to the conclusion that the athlete's heart is a balanced enlarged heart.  相似文献   
39.
BACKGROUND: Rapid, patient near tests for detecting antibodies against Helicobacter pylori are offered for clinical use. We evaluated the BM-Test (Boehringer Mannheim, Germany; identical to the Helisal Rapid Blood Test) in children with recurrent abdominal pain. METHODS: The BM-Test and 13C-urea breath test (UBT) were performed in 195 children (4-18 years). Symptoms were assessed using a 4-week diary. Upper endoscopy was performed in all UBT-positive children and in UBT-negative children with symptoms suggestive of organic disease. H. pylori status was considered positive if at least two of three methods (UBT, histology or rapid urease test) or culture were positive. RESULTS: After exclusion of children with previous H. pylori therapy (n = 8) and undetermined H. pylori status (n = 1), 61/186 (33%) children were H. pylori positive. The BM-Test in relation to H. pylori status revealed a sensitivity of 54%, specificity of 90%, a likelihood ratio of 5.2 for a positive, and of 0.4 for a negative test result. Accuracy of the test was independent of ethnicity, gender, age, family history for ulcer disease, frequency or severity of abdominal symptoms, epigastric tenderness, type of blood sampling (capillary versus venous) and DOB values of the UBT. In eight previously treated children, the test gave one false-positive and three false-negative results. CONCLUSIONS: Almost half of H. pylori-infected children and 10% of non-infected children were misclassified by the BM-Test. False-negative results are not related to young age or certain ethnic groups. The poor performance makes the test unsuitable for epidemiological and clinical use in children.  相似文献   
40.
The familial form of dilated cardiomyopathy (DCM) occurs in about 20%–50% of DCM cases. It is a heterogenous genetic disease: mutations in more than 20 different genes have been shown to cause familial DCM. LMNA, encoding the nuclear membrane protein lamin A/C, is one of the most inportant disease gene for that disease. Therefore, we analyzed the LMNA gene in a large cohort of 73 patients with familial DCM. Clinical examination (ECG, echocardiography, and catheterization) was followed by genetic characterization of LMNA by direct sequencing. We detected five heterozygous missense mutations (prevalence 7%) in five different families characterized by severe DCM and heart failure with conduction system disease necessitating pacemaker implantation and heart transplantation. Four of these variants clustered in the protein domain coil 1B, which is important for lamin B interaction and lamin A/C dimerization. Although we identified two novel mutations (E203V, K219T) besides three known ones (E161K, R190Q, R644C), it was remarkable that four mutations represent LMNA hot spots. DCM patients with LMNA mutations show a notable homogenous severe phenotype as we could confirm in our study. Testing LMNA in such families seems to be recommended because genotype information in an individual could definitely be useful for the clinician. Returned for 1. Revision: 18 February 2008 1. Revision received: 12 August 2008 Returned for 2. Revision: 20 August 2008 2. Revision received: 21 August 2008  相似文献   
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